[steve1977]

Well the theory behind it doesn’t say „blue is unhealthy or harmful“ but „blue is daytime“.

Hence the idea to filter out blue at times when there is no blue sky in nature (aka at night).

[dingaling]

Moonlight and starlight are blue-biased. There is very little red or green light at night...

[steve1977]

I'm just regurgitating the theory, I'm not saying I'm buying into it... ;)

In my personal experience (anectdata), the effects are very neglibable (to the degree they might be placebo)